The use of a multibeam motor vehicle radar system for detecting the distance and/or velocity of an object is discussed, for example, in German Published Patent Application No. 196 48 203. In the case of at least one antenna, which forms a total of at least two antenna lobes, at least one of these antenna lobes is used for transmitting and receiving radar signals, an additional antenna lobe being exclusively used for receiving radar signals.
German Published Patent Application No. 199 63 005 describes a method and a device for detecting and analyzing objects in the surroundings of a vehicle in which the objects are detected using at least one radar sensor and distance data and/or velocity data of the objects is analyzed in at least one analyzer unit. The surroundings of the vehicle are detected using a transmitted signal of a pulse radar sensor in one or more receiving branches in such a way that different distance ranges are analyzed sequentially and/or simultaneously.
The disadvantage of the known systems is in particular that a complex and bulky, and therefore cost-intensive radar system is provided, which has different individual components which must be connected in a high-frequency compatible manner. Because the operating frequencies of such radar systems will assume higher values in the future, the parasitic effects also increase due to the parasitic inductances and capacitances of the connections between the individual components according to the related art. If the discrete components such as a chip for producing an HF signal, distributing network and, mainly, antennas, are mounted onto a substrate device made of ceramic, LTCC, a circuit board or a soft board, strong parasitic effects are to be expected at high frequencies, particularly over 50 GHz, due to the tolerances in manufacturing and connections.